COMMITMENTS AND CONTINGENCIES - Obligations Under Capital and Operating Leases (Details) - USD ($) |
9 Months Ended | ||
|---|---|---|---|
Sep. 30, 2016 |
Dec. 31, 2015 |
Aug. 19, 2010 |
|
| Obligations under capital and operating leases | |||
| Total expected payments for capital and operating lease over the next three years | $ 100,000 | ||
| Period over which payments are due | 3 years | ||
| Expected payments for capital and operating lease, current fiscal year | $ 23,000 | ||
| Expected payments for capital and operating lease, 12 to 24 months | 86,000 | ||
| Expected payments for capital and operating lease, 24 to 36 months | 0 | ||
| Mining properties, land and water rights | $ 222,335,000 | $ 220,635,000 | |
| Eureka Moly LLC | |||
| Obligations under capital and operating leases | |||
| Sustainability Trust fund asset amount | $ 4,000,000 |